Semiconductor devices are typically manufactured on semiconductor wafers or other types of work pieces using sophisticated equipment and processes that enable reliable, high-quality manufacturing. The individual dies (e.g., devices) generally include integrated circuits and a plurality of bond-pads coupled to the integrated circuits. The bond-pads provide an array of external contacts through which supply voltage, electrical signals, and other input/output parameters are transmitted to/from the integrated circuits. The bond-pads are usually very small, and they are typically arranged in dense arrays having fine pitches between bond-pads. The dies are quite delicate and need to be protected from the environment and for handling. As a result, the dies are packaged to protect them and to connect the bond-pads to an array of larger terminals that are easier to connect to a printed circuit board. The packaged semiconductor components can then be electrically connected to other microelectronic devices or circuits in many types of products.
Ceramic packages are one type of packaging for semiconductor dies. Ceramic packages typically have individual ceramic units that have a cavity, die contacts within the cavity, and external terminals electrically coupled to the die contacts. The external terminals are generally on the exterior sidewall or backside of the ceramic unit. A die is positioned in the cavity, and the bond-pads on the dies are electrically coupled to the die contacts within the cavity. An encapsulant is then deposited into the cavity to cover the die.
Ceramic packages are useful in many applications, but they also have several drawbacks. One drawback of ceramic packages is that the ceramic units are generally handled individually instead of being in the form of a wafer that can be handled in wafer processing equipment. As a result, each of the individual ceramic units must be loaded into trays for the packaging process, and then unloaded for subsequent processing. This type of handling is costly and impacts the throughput of packaging processes. Ceramic packages are also relatively expensive to a manufacturer compared to other types of packages. Therefore, ceramic packages have several drawbacks.
Another cavity-type semiconductor package has a polymer riser laminated to a circuit board. For example, Kinsus Company of Korea makes a non-stacking cavity package that includes a printed circuit board having a plurality of die contacts on one side and a plurality of backside contacts on the other side. The package further includes an upper board without circuitry laminated to the printed circuit board. The upper board has openings that define cavities over the printed circuit board, but the upper board does not include any circuitry or vias. A die is mounted to the printed circuit board within the cavity formed by the opening in the upper board, and the bond-pads on the die are connected to the die contacts on the printed circuit board. The cavity is then filled with a polymer or other type of encapsulant to encapsulate the die.
Although such laminated packages are useful and relatively inexpensive to manufacture, they are not well suited for stacking packages in high-density applications. For example, such laminated packages cannot be used in stacked assemblies because these packages do not provide an electrical connection that routes power and signals to/from the upper package(s). Therefore, it would be desirable to develop a cavity-type package using laminated circuit board material for manufacturing high-density stacks with fully tested packages.